using System;
using System.Collections.Generic;
using System.Windows;
using System.Windows.Media;
using BeWo.Core;
using BeWo.Core.Commands;
using BeWo.ServiceProxy;
using BeWo.ViewModel;
using BeWo.ViewModel.ListViewModel;
using BS.Shared.Extensions;

namespace BeWo.View.Detail
{
    public partial class AbsenceTimesView
    {
        public static readonly DependencyProperty AbsenceTimesDependency = DependencyProperty.Register("AbsenceTimes", typeof(AbsenceTimeListVM), typeof(AbsenceTimesView), new UIPropertyMetadata(AbsenceTimesChanged));

        private static void AbsenceTimesChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            var view = d as AbsenceTimesView;
            var list = e.NewValue as AbsenceTimeListVM;
            if (view != null && list != null)
            {
                view.AbsenceReasonComboBox.ItemsSource = list.PossibleReasons;
            }
            
        }

        public ButtonClickCommand AddAbsenceTimesCommand { get; set; }
        public ButtonClickCommand RemoveAbsenceTimeCommand { get; set; }

        public AbsenceTimeListVM AbsenceTimes
        {
            get => (AbsenceTimeListVM) GetValue(AbsenceTimesDependency);
            set => SetValue(AbsenceTimesDependency, value);
        }

        public AbsenceTimesView()
        {
            InitializeComponent();

            DataContext = this;
            
            AddAbsenceTimesCommand = new ButtonClickCommand(AddAbsenceTimes);
            RemoveAbsenceTimeCommand = new ButtonClickCommand(RemoveAbsenceTime);
        }

        private void AddAbsenceTimes()
        {
            bool doSave = true;

            var ueberschneidungen = PruefeAufUeberschneidungen();

            if (ueberschneidungen.Count > 0)
            {
                doSave = false;
                if (MessageBox.Show(
                        "Die Abwesenheit überschneidet sich mit mindestens einer bereits vorhandenen Abwesenheit.\nMöchten Sie trotzdem speichern?",
                        "BeWo Planer", MessageBoxButton.YesNo, MessageBoxImage.Question) == MessageBoxResult.Yes)
                {
                    doSave = true;
                }
            }

            if (doSave)
            {
                AbsenceTimes?.NewVM.ValidateDates(() =>
                {
                    AbsenceTimes?.AddNewVMToList();
                });
            }
            
        }

        private List<AbsenceTimeVM> PruefeAufUeberschneidungen()
        {
            
            var neu = AbsenceTimes.NewVM;
            
            DateTime neuStart = neu.Start ?? DateTime.MinValue;
            DateTime neuEnd = neu.End ?? DateTime.MaxValue;


            List<AbsenceTimeVM> abwesenheitenMitUeberschneidungen = new List<AbsenceTimeVM>();

            foreach (var alt in AbsenceTimes.VMList)
            {

                DateTime altStart = alt.Start ?? DateTime.MinValue;
                DateTime altEnd = alt.End ?? DateTime.MaxValue;

                if (neuEnd >= altStart && neuStart <= altEnd)
                {
                    abwesenheitenMitUeberschneidungen.Add(alt);

                }
            }

            return abwesenheitenMitUeberschneidungen;
        }

        
        private void RemoveAbsenceTime()
        {
            AbsenceTimes?.VMList.Remove(DataGridAbsenceTimes.GetCurrentValue<AbsenceTimeVM>());
            BeWoWpfUtils.RefreshDXGrid(DataGridAbsenceTimes);
        }

    }
}